How do you persuade parents to buy you a laptop?

Hi I am 14 years old and my parents just got me a new laptop with Windows vista on it a while ago. I had told my parents that I wanted a macbook but they kept trying to get me to get a pc, so I did. Now I regret that so much because im about to kill myslf from all of vistas bugs. My comp wont shutdown sometimes even! When I first got it I got the Blue screen of death everytime i turned it on! Anyway my bro wants my laptop and I want a new macbook. My bro was gonna get a laptop anyway so it wont make a difference financially. Anyway I need a way to convince my parents to get me the macbook this will be realy hard cuz my dad has never used a mac and doesnt know how good they r like i do. Thanx for your help!How do you persuade parents to buy you a laptop?
For one you can tell them how integrated the Mac OS is, and how it will help with school, and that it can also run Windows. Tell them that Mac OS X is very secure with 'Filevault' features built in that let you encrypt important files, and that there are NO Mac viruses. (Macs aren't invulnerable to viruses though, and can still spread viruses without knowing it...you may want to leave that part out.) Good luck! The Macbook laptops are super overpriced.How do you persuade parents to buy you a laptop?
If you have a laptop, why do you want another laptop? You should of told them to get a Macbook.